Tay TKY, et al. - The molecular genetics of pediatric breast fibroepithelial tumours were examined through targeted sequencing of 50 genes. Using the Haloplex Target Enrichment System (Agilent), they subjected formalin fixed paraffin embedded tissue of fibroepithelial tumours diagnosed in a cohort of patients aged 18 years and below to next-generation sequencing. Findings reveal that paediatric fibroepithelial lesions having cellular stroma may potentially raise concern for phyllodes tumour, while their lack of TERT promoter and cancer driver mutations is reassuring. A significant proportion of tumours, especially the giant fibroadenomas, were lacking mutations warranting investigation of pathogenetic mechanisms beyond the 50 genes.